Selective signaling system.



UNITED sTATEs PATENT OFFICE.`

BICBARJ? C. LEAKE, OF ROCHESTER, NEW

SIGNAL COMPANY, 0F GATES, NEW YQIRI'L A CORPORATION 0F NEW Yonx, AssmNoE To GENERAL `namwnr YRE.

SELEOTIVE SIGN LING SYSTEM.

Specication of Letters Patent.

Patented Dee. 19, `191e.

Application tiled December 11, 1914. Serial No. 876.836.

To all wftom z't may concern Be it known that I,.R1CHARD C. LEAKE, a citizen of the United States, and a resident of the city of Rochester, in the county of onroe and State of New York, have invented a new and useful Improved Selective Signaling System, of which the following is a specification.

This invention relates to an improved selective signaling system, and particularly to such a s stem in which a distinctive answer back in ication is 'given to the 'operator at a central station, who has caused the movement of a signal at a remote oint, that the signal has actually assumed tie position intended.

The primary object of this invention is to inform the operator of a selective signaling system by means of a preliminary indica.- tlon, of t e characteristic answer back indication which is to be received by him dueA to the changing by him of the position of a remote controldevice.

Other objects and advantages will appear as the description of the invention progresses, and the novel features of the inven-Av tion will be particularly pointed out in thei appended claims.

In describing the invention in detail, reference is had to the accompanylng drawing, lwherein I have illustrated a preferred physL ical embodiment of my invention, Iand u1 which the figure illustrates schematically a preferred arrangement whereby the invention may be practised.

.As iswell known to those skilled in the` art, selective signaling systems are old and wellkn'own which comprise a series of ,signals located at points remote one from the other, and from a centrzll point. each of which signals is selectively controlled yfrom the said central point over two line wires, and which have associated'with each signal a device automatically operated by the i changing` of the position ofthe signall which causes what is known as an ausuer'back indication ,to be sent back over the line wires upon a changing of position of the signal to notify the operator at the central point that the signal which he intended to operate did actually operate, and did actually assume the position intended. These systems which are old in ythe art, also in generiil [include Adevices known as Findividiial. calling keys located at they central VLpoint, which are so arranged and construct# lcompleted lts change of position and key 'certain disks having circuit making teeth in their periphery, as fully shown and described in the patent above referred to.

As each key is individual to each signal, and each signal gives a characteristic answer back, applicant has taken advantage of such fact by causin eachkey to produce, before the ey has entirely completed its movementLand before the signal governed by the key has actually encrated its characteristic answer back, tg itself generate the same characteristic answer back as that which will almost immediately thereafter be enerated by the signal itself, so as to there y inform the 0 erator as t0 the particular answer back w ich he must obtain.

`the o eration of Q 0n account ofthe fact that-each Signal generates a dil'erent answer back indication and there are often, despatcher, a large number of signals it cannot be expected that an operator will be able to remember the various answer back indications he sh uld receive as "a resultv of operating each individual calling-key and it seems very likely that an operator would, sooner or later, make a mistake by accepting 'a wrong answer back indication. The applicant hasin the invention herein described furnished a means which prevents any .possibility of the operator making ysuch an error due to faulty memory by causing a churactcristic preliminary indication, when the calling key is operated, whic the same code as the answer back indication which he should receive immediately thereafter upon the proper operatin ofthe signal.,

In order to illustratethe invention appli 1015l tion, but has merely shown diagrammati- 110 under the control of the is of exactly 10i0vv -selectors, is also used cally a pair of line wires which in practice are carried throughontthe system, a selector and an answer back mechanism connected across seid line wires and a signal governed by said 4selector and controlling said answer back mechanism. Neither is the particular type of individual key material to appli cants invention, and consequently applicant has illustrated in a schematic way a key which when practically formed may be con sidered similar to that shown and described in the patent. above referred to.

In the drawing the wires 1 and 2 designate the ordinary and wellknnwn line wires which extend from a central or operator-s station to the Various signal stations as described.

As is usual, the telephone receiver 3 is connected in bridge of the line wires 1 and i5 because, as is well known `to those skilled in the selective signaling art, the line wires l and 2 by which current flows to govern the as the telephone circuit'by which communication is had between the central station and the various signal stations.

In the drawingr the selector, answer back mechanism and signal hcreinbel'orc referred. to which are located at one station are shown diagrammatically. The selector is bridged across the line wires 1 and Q by wires 59 and 60 and is arranged to control the answer back r chanism A B by circuits illustrated schemioally as comprising two wires ul. and Gt?. The selector l also controls the signal l1 by circuits which are shown as coinprisiu.' iresl, 62, ('13 and (lig and the" un swer lr l mechanism A B in turn is gorcrned bythe' signal S by circuits represented by the` wires 63 and 64, T'he answer back mechanism A B is bridged across the line wires 1 and El by the Wires (i5 and Gli. It should be clearly understood that no par ticular c onstructwn of the select-or S, answer beu-l: mechanism A B or the signal E is necessary for use with this invention, and 'any construction orarrangement of these parts will be suilicient which ie suitable for enabling! the operator at the central station to control the positions o't the signal E and which causes answer batik indications of the position ofthe signal ll to be sent to the central station. One arrangement and construction .of these parts is disclosed in the Signal Engineer on page 213 and the following. pages of the .Tuly 19151 issue.

The means shown for transmitting selective impulses to the line wires 1 andvZ for operating the selector S is illustrated b v means of the conventional disksl A. ll and (,='which,"as actually constructed. may be of the form illustrated in the patent above reterred lib. and numbered therein' as 59. 63 and 61.; As is usual in selective signaling,r systems, the rather high potential battery 13 does notl have its current broken by means of the disks A, B and C, but is broken b means of the pole changing switch S, which is controlled by the polarized relay T, which is in turn controlled by the. disks A, B and C. The im )edances .8, l), l() and 11 and the condensers and 12 are the ordinary and well known expediente to 'p1-event undesired interference with the telephone receiver 3.

As fully shown and described ,in the pat-- ent hereinbefore referred to, the disk A has teeth 17 thereon, three in number, which upon rotation of the disk A, Contact with the.spring-14, and so cause one coil of the polarized relay T to be alternately energized and denergized by a circuit' which may be traced as follows: one terminal of the battery 21, wires 2Q and 23, disk A, teeth 1.7, spring lil, extension 14 of spring 1.4., wire A, coil of polarized relay T, and wires 26 and 27 to the other terminal ol' the battery 21. Current flowing iu the above traced path causes the right hand end of armature 538 to be raised, and so causes the arm attached to said armature to move the conducting arms and 3l) to the left from their mid-position, as shown, so that they connect. withthewires 33 and 31 respectively, thereby allowing current to liow from the battery litoithe line wires 1 and 2.

,As fully shown and,y described in the pat-` ent above referred to, after the teeth 17 have finished contacting with spring 14, the teeth 18 on ,disk B, begin to make and break con tact with spring 15, and thus cause' an alter nate energization and denergization of the cnil 28 of polarized relay T, so that current liows through said coil in a path follows: one terminal'lof the battery 21, wires 22, 38 and 43, disll B, teeth 18, s ring 15, wire 41, coil 28 and wirr-sill? and 2 to the other terminal of the battery 21. Current flowing in the above traced path causes the left hand end of armature 58 to be raised and thereby causes the arm attached thereto to more the conducting arms 29 and 30 to the right of their mid-position, as shown in the figure, into contact with wires 31 and 32 respectively. thereby allowing current to How from the battery 13 to the linewires 1 and 2, but in a reverse direction from that caused by the movement of the conducting arms' 29 and 30, to the left of their mid-position, as Y shown.

ln order to show an individual callin l cvv similar in all respects to that shown an described in the patcnt above referred to, applicant has also included the disk C in the figure, which has one tooth 19 on its periphery, which, as fully described in the patent above) referred to. makes Contact with the same spring 14, that the teeth on the disk A make eontactwith, but shown in the figure of the drawing' as two Separate springs .for greater clarity. The tooth 19 on the disk C makes contact with spring 14 after the teeth 18 on the disk B have finished making contact with the spring 15. The

.6 the left of their mid-position, as shown on the figure-so that they contact with. wires 33VA and 31 respectively, thereby allowing current to flow from the battery-13 to the -line wires 1 and 2 in the same direction that it was caused to How bythe contact of the teeth 17 of disk A with the spring 14, thereby Afinishing the sending of those impulses to the 4line wires 1 and 2 necessary to operate a selector of the type mentioned and schematically illustrated in the patent hereinbefore referred to. y'

rAll of the devices hereinbcore described and explained are old and well known in the art, and contain no features of novelty attempted to be covered by this application.

To the same shaft 57 to which th disks `A, B and C are rigidly attached, `is also rigidly attached a disk D, which conseuently must revolve in synchronism with the other disks, and must complete its rota tion simultaneously with. the completion of `the rotation of the other disks A., B and C, so that, as will be well understood by those skilled 'in the art of selective signaling. it must'zcomplete its movement before .a seins- Y phore signal E controlled by a selector S, auch as is schematically shown in the patent hereinbefore referred to, has assumed a new osition due to the operation of such seector S, andoconsequently before such signal E can have., returned an answer back indicat ion over the line wires 1 and 2 to the telephone 3 at the central station. The rotation-of disk D causes the teeth 20 ou the periphery thereof to engage with the spring' 16, thus alternately breaking and making a circuit .which may be traced las follows: one terminal of the batterv 2l, wires 22. 3S. ISS) and 40, disk D, teeth 20,'spring lo, wire 45,

contact point 46, spring` biased armature i7,

, primary of an Induction coil 4S. and wires y 50 and 27 to the other tvrmiualcf the hattery 21. Current flowing in the above traced path causes, as is well understood bv those .skilled in the electrical art, thc rapid vibration of armature 47, so thatan alternating current is thereby produced in thesecondary coil 49, which, by means of wires 51 and 52 through the condensers 53 and 54 and wires 65 and liti, is transmittedto wires 37 and 34,

olarized fbe, a lar e number .could not clearly which are directly connected, through the reactance coils 9 and 8 to the wires 36 and 35, which connect throu h wires 6, 5, 4, and condenser 7 to the telephone receiver 3. The alternating Vcurrent generated in the secondary coil/i9 is transmitted by the connection above described, to the telephone receiver, thereby causin an operation thereof in the nature of au ible clicks, as many in number as there are teeth on the disk D, so that there is produced upon the ear of a` listener at receiver 3 a characteristic series of sounds.'

In the practice of applicants invention, although there may be, and probably will `of signals to .be controlled, tiere will be a key individual to each signal for the control of that signal only. Attached to the shaft bearin the. impulse disks of eaclrkey will be a r isk having teeth formed in its periphery of such number, and in such spaced relation as will generate in a receiver as 3 the same code impulses or audible clicks as will be produced by the .particular signal governed by that key in generating an answer back set of impulses for notifying the operator at the central station that the signal has actually assumed the position intended. i

Most of the answer back mechanisms act `by sending to the central station a series of dlrect current impulses. Such impulses, acting upon a telephone receiver, causea peculiar tone of click which can be easily recognized by one at all expert as being cruised by a direct current. It is advisable to have the tone of the clicks produced in the receiver bythe preliminary indication caused by the rotation of the calling key clifl'erent'from `the tone of the clicks produced by the. answer back mechanism. A plicant has accomplished this object by mah ing use oi. the induction coil having the primary 48 andthe secondary 49. That is, instead of sending a series ofV direct current impulses to the lintl wires 1 and 24 to produce a preliminary indication by the rotation of the disk D, these impulses are caused to flow through the priniaigv of an .induction coil, thi-roby producing in the secondary of that coil au alternating current which is their caused to aifert thc telephone `receiver 3. The tone of thc clicks thus generated in `the receiver 3 are distinctively different from the tone of the clicks produced in., the res ceivor Il by the direct current impulses transmitted to the `line wiresby the answer back device itself. This expedient obviates any diiiiculty which might arise if the operator distinguish the .preliminary indication from the actual indication which he is to receive later.

Although I have Qparticularly described the construction of one physical embodiment of my invention, and explained the operation and principle thereof; nevertheless, I desire to have it understood that the form selected is merely illustrative, but does not exhaust the possible physical embodiments of the idea of means underlying my invention.

What I claim as'nevv and desire to secure by Letters Patent o'f the United States, is:

1. In a selective'signalin system, in coin- 'bination a remote control evice; means for controlling said remote control device from a chntral station; means controlled by said remote control device for 'ving a code indication at the central station of the movements of said remote control device; and means operated by said first mentioned means for giving preliminarily at the central station, the same code indication distinctive from the indication given by the means controlled by said remote control device.

2. In a. selective signaling system, in com bination: a remote control device; means for controlling said remote control device from a central station; a pair of line wires; a telephone receiver bridged across said line Wires and adapted to-receive indications from said line wires; means controlled by said remote control device for sending a code indication over said line wires to the tele hone receiver for each movement of sai device; and means operated by said iii-st mentioned means for giving preliminarily at the central station an indication of the same code as the first mentioned indication but of a different tone.

3. In a selective signaling system, in combination: a remote control device; a selector for controlling said remote control device; an impulse transmitter for controlling said selector from a central station; a pair of line wires; means controlled by said remote control device for giving a code indication over said line wires at the central station, of the movements of the remote control device; and means operated by said impulse transmitter for giving preliminar-ily at the central station an indication of the same code over'said line Wires,5 distinctive from the indication given by the?, means contr- Aled by saidrelmote control device.

4. In aiselective signalinsystem, in combination: 'a remote control1 eviceg a selector for controlling said. remote control device; aniimpulse transmitter for controlling said selector from a central station; a pair of line wires; means controlled by said remote control device for giving over said line wires to the central statioma code ndication of the movements of the said remote control device; vibrating means for giving preliminarily at the central station the sume code indication distinctive from the indication given by the means controlled by said remote control device; means governed `by said impulse transmitter for operating' said vibrating r'eans subsequent to the operation of said impulse transmitter; and a telephone receiver bridged across said line wires for receiving said indications.

5. In a signaling system, in combination: two line wires; a telephone receiver bridged across said line Wires; atremote control device; means governed by said remote control device for sending over said line wires to a central station a code indication of the operated condition of said device; a selector for governing said remote control device; a

calling key for controlling said selectorg means operated by said calling key for ap plying to said line wires impulses in the same code as said indicationpand means for modifying the electrical character of said impulses, whereby said impulses can be distinguished from the indicatin given by the means governed by said remote control device.

(5. In a signaling system, in combination: a, remote control device; a selector for controlling said device; a pair of line wires; a telephone receiver bridged across said line wires a source of energy; an impu'sle trans mitter for governing the connection between said source of energy and said line wires and governing said selector by the impulses sent over said line wires; answer lief-lc mechanism controlled by said remote cont; il device for sending code indications over i `d line wires indicating the movements of said remote control device; a local circuit t the central station connected to said lin wires; means governed by said impulse transmitter for applying to said local circuit a` preliminary indication of the same code as that sent by said last mentioned means; and an induction coil included n said local circuit for xnodify.-Y

ing the current therein, whereby said preliminary indication is distinctive in tone from the indication sent by said answer back mechanism.

7. In a selective signaling system, in combination: two independent means for sending the same code indication distinctive in tone over the same line wires to a common receiving point; and means for governing 

